Now, she's speaking out about an experience last December that left her reeling.

She was taken aback when, in the middle of a routine holiday shopping trip to Walmart, an employee discouraged her from trying on a sweater because she "would stretch it." When the incident first happened, she only shared a brief few sentences about it on her YouTube channel, promising to post a full video about the situation in the future. Now, she's finally opening up about the experience and urging others to fight back against discrimination when they see it.

She captured her encounter with the fat-shaming employee on camera.

The footage shows a store employee snatching a sweater out of Friesen's hands when she attempts to take it into a fitting room. When Shiann asks the employee to clarify, she says "Just don't try to push it...Just don't try to put on something that's obviously not going to fit. That's all I'm asking. Just don't stretch it. That's all I'm asking." Suddenly noticing that she's being filmed, the woman adds "I'm not trying to be impertinent or anything."

In a video shared on her YouTube channel, Friesen says that she saw the woman discriminate against other customers a few minutes later. "I felt vulnerable and almost like I was 'naked in a crowd,' so to speak," she said in the video. "I don't think the situation needs much explaining. The words that came out of her mouth did enough of that."

"I was so shocked I had to ask her to repeat what she had said, because maybe I would hear it differently," Friesen told People. "And of course, I didn't. But I quickly recognized that I was being discriminated against, and I was hurt. I felt anger, and vulnerability; something I never would have expected to happen to me...People have had their opinions on what I should put on my body, but never have I been denied the right to try on an item."

Friesen told the employee that what she was doing was discrimination.

Walmart representatives have been incredibly supportive, according to Friesen. "Every single person from the Walmart team I talked to has been extremely sorry and extremely shocked that this even happened at one of their stores," Friesen told People. When ** the magazine reached out to Walmart Canada, the company said it was currently working on contacting Friesen.

"The only thing we know of at this point is the video," Alex Roberton, Walmart's senior director of corporate affairs," told People. "But there's no record of her reaching out to the store or to head office at this point." When told that Friesen had already contacted the company, he replied: "One of our core beliefs is respect for the individual, that's certainly paramount. So obviously whoever she talked to [at Walmart corporate] is reacting appropriately. I just don’t have a record of those conversations here. We'll continue our efforts [to reach Friesen] on our end." When asked about whether the employee would be terminated, he said the company "wouldn't discuss that publicly."

Sharing the story was a vulnerable move, but she decided to make it public to help others understand the importance of fighting discrimination and knowing their rights.

"People need to be educated that discrimination can happen to anyone," she told People. "I am hoping this gives people the confidence to stand up to injustice and discrimination. It is my mission to teach people they have worth, and need to pride themselves enough to stand up and speak out about injustices in the world, that is my duty as a human."